Weidmann addressed an economists' conference in Aix-en-Provence, southern France, only three days after the ECB broke with precedent by declaring that it intended to keep interest rates at record lows for an extended period and may yet cut further.

"Monetary policy has already done a lot to absorb the economic consequences of the crisis, but it cannot solve the crisis," Weidmann said in his speech.

"This is the consensus of the Governing Council. The crisis has laid bare structural shortcomings. As such, they require structural solutions."

Weidmann, widely recognised to be the most hawkish member of the ECB's 23-man Governing Council, does not want the bank to intervene too strongly in tackling the bloc's economic crisis, thereby allowing governments to soft-pedal reforms.

He spoke a day after fellow ECB policymakers Christian Noyer and Benoit Coeure said the bank's decision to abandon its customary insistence that it never precommits on policy was a change in communication but meant no change from its strategy, which is based on monitoring inflation, real economy and monetary developments.

"The euro zone is on the mend, it must be at peace, protected, be allowed to heal," Coeure told the same conference on Sunday to explain the ECB's decision to issue such forward guidance, while urging governments to tackle structural problems.

The EU's top economic official, Olli Rehn, welcomed the ECB's move, saying the step - taken in response to turbulence caused by the U.S. Federal Reserve's plan to slow monetary stimulus - was needed to preserve recovery in Europe.

"The United States and Europe are at different points of the economic cycle. While the U.S. has a more restrictive approach, Europe needs to continue with a more accommodative policy," the EU monetary affairs commissioner said.

FISCAL RULES

While he does not see sufficient support in the euro zone for governments to give up sovereignty on fiscal matters to forge a fiscal union to prevent such crises in the future, Weidmann pressed them to stiffen Europe's fiscal rules.

"To fully unleash the common currency's potential, efforts are needed on two fronts: structural reforms as well as the abolition of implicit guarantees for banks and sovereigns (government bonds)," Weidmann said.

"In addition to stronger rules, we need to make sure that in a system of national control and national responsibility, sovereign default is possible without bringing down the financial system. Only then will we really do away with the implicit guarantee for sovereigns."

The Bundesbank chief also called for euro zone governments to sever what he describes as the "excessively close links" between banks and sovereign governments, saying that European banks hold too many of their own governments' bonds.

"This is because banks do not have to hold any capital against their government debt, as the risk-weight assigned to sovereign bonds is zero.

To counteract excessive investment in sovereign bonds, Weidmann believes that the capital rules need to be changed to take account of risk and exposure levels.

"Only then will banks be able to cope with the repercussions of sovereign default." (Writing by Paul Carrel; Editing by Alison Williams)